I have a YN565-EX, which is fully CLS compatible, and it worked out great value for money.

I am not personally familiar with the Meike, so can make no hands-on comparison. The build quality of the YN is beyond reproach. The battery compartment door is actually superior to the SB600's, IMO, spring-loaded and more substantial. I wish it had Nikon's Speedlight-to-camera locking mechanism, which I think I saw the Meike SB900 copy has.

The YN has S2 slave functionality, which enables a poor man's 3rd CLS group. I have 2 SB600s, so use one in each of Group A & B for portraiture and use the YN in manual S2 mode on the background, where less changes are required.

Note that the YN has no Master functionality, but even the SB700 only offers the 2 groups my D90 has in the body, albeit likely at higher power levels.

The new Meike SB900 copy will talk to 3 groups (as a Master), as far as I know, but can't handle high speed synch.